In mobile communication devices that include two microphones, non-stationary or ambient noise may be suppressed by positioning the two microphones of the mobile communication device at a predetermined distance from one another. For example, a primary microphone of the mobile communication device may be located proximate to a bottom end of the mobile communication device so that the primary microphone is as close to a mouth of a user when the mobile communication device is used by the user. A secondary microphone of the mobile communication device may be located on a back surface of the mobile communication device to achieve a predetermined amount of natural dampening in speech received at the primary microphone when the mobile communication device is used by a user. This two microphone configuration results in speech received at the primary microphone being significantly louder than speech received at the secondary microphone when a user speaks directly into the primary microphone. Known non-stationary noise suppression processes, such as those based on beam forming principles, may be utilized to suppress non-stationary or ambient noise received in a speech signal generated at the primary microphone while keeping the generated speech signal intact. Such known non-stationary noise suppression processes, however, have limitations. For example, when a primary microphone and a secondary microphones of a mobile communication device receive speech from a user that has the same level, known non-stationary noise suppression processes treat the speech signal generated at the primary microphone as ambient noise and hence attempt to suppress this speech signal, which causes unwanted muting of the speech signal generated at the primary microphone. Improvements in non-stationary or ambient noise suppression process are therefore desirable.